Freshwater Biomes

Four different freshwater ecosystems Ponds/Lakes Streams Rivers Wetlands: marshes & swamps

Freshwater Biomes Freshwater contains less than 1% salt. The main abiotic factors that determine the type of aquatic biome are: sunlight, temperature and salinity. Sunlight and nutrients determine the distribution of organisms. The warmer the water the more life, the more food the more life.

Ponds and Lakes Scattered all over Can be a few square meters to square kilometers Ponds seasonal, lakes can last hundreds of years 4 main zones Littoral Limnetic Profundal Benthic- bottom or floor

Freshwater zones:

Littoral Zone: Located at the land at the edge of the water, shallow Warmest water Receives the most sunlight Flora: cattails, rushes, water lilies, & weeds, plants rooted to the bottom Fauna: snails, insects & larvae, clams, worms,, frogs, salamanders, turtles, fish, & snails Pass around container with insect larvae in it and fake water lilies for students to observe

Open Water Zone or Limnetic Zone Located from the littoral zone across the top of water & goes as deep as light can reach, shallow water Fauna: plankton, and fish, algae, microscopic Crustaceans, bass and trout Plankton are small organisms that play a crucial role in the food chain.

Profundal Zone Deep Water Zone Deepest freshwater zone Coldest water No light in this zone Fauna: catfish, carp, worms, insect larvae, fungi, bacteria, crustaceans All of these are bottom feeders and eat the dead things that fall to the bottom

Benthic Zone Benthic Zone is the area at the bottom of a lake or pond The bottom is covered with dead and decaying plants and animals Also covered with a layer of sediment